It's 'Hamlet's broom' instead of 'Hamlett's Broom'.
The height after 10 years of this broom from Danmark will be about 2,5 metres.

I hope I helped you with this info...

Thank you very much for the growth info and the name correction. (Now I need to move it to a different spot; I was assuming that it will be as big as the species.)
You are most helpful as usual.